[KUDU-2168] Add support for unique constraints

• Type: Wish
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Component/s: client, master, tablet
• Assignee: Unassigned
• Reporter: Roger Marin
• Created: 05/Oct/17 00:19
• Updated: 02/Jun/20 20:41

Description

Kudu currently supports unique constraints via primary keys but some times a unique value constraint on (nullable) arbitrary column(s) independent of the primary key column(s) may also be required.

Example impala syntax:

CREATE TABLE my_first_table
(
  id BIGINT,
  name STRING,
  unique_val_1 BIGINT,
  unique_val_2 BIGINT,
  PRIMARY KEY(id)
  UNIQUE CONSTRAINT(unique_val_1,unique_val_2)
)
PARTITION BY HASH PARTITIONS 16
STORED AS KUDU;

Example api syntax:

val kuduTableSchema = StructType(
   StructField("id", IntegerType , false) ::
   StructField("name" , IntegerType, true ) ::
   StructField("unique_val_1", IntegerType , true ) ::
   StructField("unique_val_2", IntegerType , true ) :: Nil)

val kuduPrimaryKey = Seq("id")
 
val kuduTableOptions = new CreateTableOptions()
kuduTableOptions.
 setUniqueConstraintColumns(List("unique_val_1", "unique_val_2").asJava).
 setRangePartitionColumns(List("name").asJava).
 setNumReplicas(3)
 
kuduContext.createTable(kuduTableName, kuduTableSchema, kuduPrimaryKey, kuduTableOptions)

Issue Links

• is blocked by: KUDU-2613 Implement secondary indexes